It is my belief that “if” there was a big bang it was simply the same process on a universe scale that happens to a star.
It forms, condenses via gravity, then eventually explodes and the cycle repeats.
My guess is that our universe is simply 1 among an infinite number of universes much like the stars are in a single universe.
Bingo.
Question; In all of nature (that we can observe) where is there only ONE of anything?